FIELD OF INVENTION
[0001] The present invention relates to an encapsulated dye composition for detergent powder.
In particular the present invention relates to non-bleeding dye composition encapsulated
in a carrier, method for the preparation of said encapsulated dye composition and
detergent compositions comprising the same.
BACKGROUND OF INVENTION
[0002] Incorporation of the colored pigments in the detergent powder has increased for the
past few years. The colored particles enhance the appearance of the detergent powder,
as well as may have effect on the fabric conditioning.
[0003] The colored particles used in the detergent powder mostly comprise of the colorant
such as dye. The use of dye stuff as colored material is associated with flaws. Conventionally
used colored particles tend to bleed the dye in the detergent powder and therefore
tend to convert the colour of the white powder. This may affect the customer base
for that particular detergent powder.
[0004] Additionally, the dye gets stuck in the fabric and does not shed off the fabric thereby
affecting the fabrics.
[0005] US-20110053823 discloses colored speckles comprising a porous material, a releasing agent, and a
dye. This patent describes the colored speckles which quickly release color from the
porous carrier using releasing agent and provide desirable color to the wash water.
The releasing agent is selected from the group consisting of salt compounds, sugar
compounds, alkoxylated aromatic compounds, glycols, high molecular weight alcohols,
solvents having a boiling point above 60°C, and mixtures thereof.
[0006] WO-0210327 discloses colored speckles comprising sodium chloride and colorant. It discloses
presence of significant amount of hygroscopic material i.e. sodium chloride (at least
90%) in the matrix. This could cause the bleeding of dye in powder detergent under
humidity in storage.
[0007] To overcome the disadvantages associated with the prior art, the present disclosure
provides the encapsulated dye composition that does not bleed in the detergent powder
and shed off the fabric easily during washing.
SUMMARY OF INVENTION
[0008] According to an aspect the invention provides an encapsulated dye composition comprising
a dye, a carrier consisting of a mixture of silica and clay and optionally a binder.
[0009] In another aspect the present invention provides methods for the preparation of the
encapsulated dye composition.
[0010] According to another aspect the present invention provides a detergent composition
comprising encapsulated dye composition of the present invention.
[0011] According to another aspect the present invention provides a method of laundering
fabrics which includes a step of treating the fabrics with encapsulated dye composition
of present invention.
DETAILED DESCRIPTION OF INVENTION
[0012] For the purposes of the following detailed description, it is to be understood that
the invention may assume various alternative variations and step sequences, except
where expressly specified to the contrary. Moreover, other than in any operating examples,
or where otherwise indicated, all numbers expressing, for example, quantities of ingredients
used in the specification are to be understood as being modified in all instances
by the term "about". It is noted that, unless otherwise stated, all percentages given
in this specification and appended claims refer to percentages by weight of the total
composition.
[0013] Thus, before describing the present invention in detail, it is to be understood that
this invention is not limited to particularly exemplified process parameters that
may of course, vary. It is also to be understood that the terminology used herein
is for the purpose of describing particular embodiments of the invention only, and
is not intended to limit the scope of the invention in any manner.
[0014] The use of examples anywhere in this specification including examples of any terms
discussed herein is illustrative only, and in no way limits the scope and meaning
of the invention or of any exemplified term. Likewise, the invention is not limited
to various embodiments given in this specification.
[0015] Unless otherwise defined, all technical and scientific terms used herein have the
same meaning as commonly understood by one of ordinary skill in the art to which this
invention pertains.
[0016] Weight percentages (wt.% or %wt) herein are calculated based upon total weight of
the composition, unless otherwise indicated.
[0017] It must be noted that, as used in this specification and the appended claims, the
singular forms "a," "an" and "the" include plural referents unless the content clearly
dictates otherwise.
[0018] The terms "preferred" and "preferably" refer to embodiments of the invention that
may afford certain benefits, under certain circumstances. However, other embodiments
may also be preferred, under the same or other circumstances.
[0019] Furthermore, the recitation of one or more preferred embodiments does not imply that
other embodiments are not useful, and is not intended to exclude other embodiments
from the scope of the invention.
[0020] As used herein, the terms "comprising" "including," "having," "containing," "involving,"
and the like are to be understood to be open-ended, i.e., to mean including but not
limited to.
[0021] In one aspect of the present invention, there is provided an encapsulated dye composition
comprising:
- a) a carrier material consisting of a mixture of silica and clay; and
- b) at least one dye entrapped in the carrier.
[0022] The encapsulated composition of the present invention further comprises a binder
such as a surfactant or a polymer. Suitable surfactant includes nonionic, anionic,
cationic or amphoteric surfactants. Examples of suitable nonionic surfactants are
polyoxyethylene sorbitan esters, polyoxyethylene sorbitol esters, polyoxyalkylene
fatty alcohol ethers, polyoxyalkylene fatty acid esters, alkoxylated glycerides, polyoxyethylene
methyl glucoside ester, alkyl polyglucosides, EO-PO blockpolymers or combinations
of two or more thereof.
[0023] Examples of anionic surfactants are sulfonates of alkylbenzene-sulfonates, alkanesulfonates,
olefinsulfonates, alkyl ether sulfate, alkyl sulfate, sulfo-succinates, alkyl phosphates,
alkyl ether phosphates, protein fatty acid condensates, perferably collagen hydrolysates
modified with fatty acid, amino acid-based surfactants, isethionates, taurides, acyl
lactylates, neutralized fatty acids or combinations of two or more thereof.
[0024] Examples of cationic surfactants are esterquats, ditallow dimethyl ammonium chloride,
C12/14 alkyl dimethyl benzyl ammonium chloride, alkyl dimethyl benzil ammonium chloride,
cetyl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, behenyl trimethyl
ammonium chloride alkyl hydroxyethyl dimethyl ammonium chloride, distearyl dimethyl
ammonium chloride, dihydrogenated tallow fatty alkyl dimethyl ammonium chloride or
combinations of two or more thereof. Examples of amphoteric surfactants are alkyl
amphoacetate, alkyl amidopropyl betaine, alkyl amidopropyl dimethylamine betaine,
undecylenamidopropyl betaine, alkyl dimethyl amine oxide.
[0025] Examples of polymers are cellulosic polymers such as hydroxyl propyl methyl cellulose
(HPMC), carboxy methyl cellulose (CMC); polyvinyl alcohol (PVA) polymers:polyvinyl
acetate (PVAc) polymer and any combinations thereof. Optionally TiO
2 dispersion may be added to enhance whiteness.
[0026] In an embodiment of the present invention, the binder is hydroxyl propyl methyl cellulose
(HPMC).
[0027] In an embodiment of the present invention, the dye is selected from the group consisting
of azine dye for example anionic azine dye, cationic phenazine dye; triarylmethane
dyes for example triphenyl-methane dye; anthraquinone dye; azo dye, disazo dye; phthalocyanine
dye; quinophthalone dye; methine dye; hemicyanine dye; azo/azomethine complex dye;
triphendioxazine dye or a mixture thereof.
[0028] In an embodiment the dye is selected from the group consisting of Duasyn Acid Violet
4BN-IN (C.I. Acid Violet 17), Duasyn Violet SP-IN (C.I. Direct Violet 66), Duasyn
Red N-6B-IN (C.I. Acid Violet 54), Duasyn Violet FBL-IN (C.I. Acid Violet 48), Duasyn
Red Violet E2R-IN (C.I. Acid Violet 126) or mixtures of one or several of the afore
mentioned dyes.
[0029] In an embodiment, the silica is at least one selected from a silica gel, pyrogenic
silica and precipitated silica.
[0030] In an embodiment the precipitated silica is hydrophilic precipitated silica, hydrophobic
precipitated silica or a mixture of both. Precipitated silica is typically produced
by a precipitation of a sodium silicate with a mineral acid under neutral or slightly
alkaline conditions. For the final application the filter cake of precipitated silica
is dried and ground. Hydrophilic silica adsorbs water around the dye and hydrophobic
silica does not allow water to get into touch with dye.
[0031] In an embodiment of the present invention, the silica is hydrophilic precipitated
silica.
[0032] The hydrophilic silica only consists of SiO
2 and does not exhibit any surface modification and is wettable by water.
[0033] In a preferred embodiment of the present invention, the hydrophilic silica has a
particle size d50 determined by laser diffraction of at least 50 µm, preferably at
least 70 µm, mostly preferred at least 90 µm.
[0034] The precipitated silica is selected from the group consisting of Sipernat® 22; Sipernat®
50 from Evonik Industries, Ibersil® D 100 or Ibersil® D100P form the IGE Group, Flo-Gard®
SC-72, Flo-Gard® LPC from PPG. The precipitated silica of the inventive formulation
is characterized by a high liquid absorption capacity, determined as DOA absorption
number of at least 120 ml/100g, preferably at least 140 ml/100g, mostly preferred
at least 160 ml/100g precipitated silica. DOA is the abbreviation for di-(2-ethylhexyl)
adipate (
CAS-number 103-23-1). The test method is based on ISO 19246 ("Rubber compounding ingredients- Silica
- Oil absorption of precipitated silica").
[0035] Hydrophobic silica is not wettable by water and exhibits an organic surface modification
created by chemical reactions with reactive alkylsilanes. The existence of such a
surface modification can be proven by various analytical methods, e.g. the carbon
content in an elemental analyzer following ISO 3262-19. In an embodiment the precipitated
silica or one of the precipitated silica used in the formulations has a hydrophobic
surface.
[0036] The hydrophobic precipitated silica for the inventive formulation is characterized
by a particle size d50 determined by laser diffraction (laser diffraction based on
ISO 13320) of at least 5 µm, preferably at least 7 µm, mostly preferred at least 9
µm.
[0037] In an embodiment the hydrophilic silica is Sipernat® D17 (d50 -10 micron) or Sipernat®
D10 (particle size -d50 -6.5 micron, free flowable) or combinations thereof.
[0038] As used herein, the term "clay" refers to both natural clays as well as modified
clays. Modified clays in this context refers to natural clays which have been alkaline-activated
or acid-activated. As used herein, the terms "clay minerals' or "special clay minerals"
refer to natural clays.
[0039] In an embodiment the clay used in the present composition is selected from the group
consisting of natural clays comprising bentonite, montmorillonite, beidellite, saponite,
hectorite, stevensite, kerolite-saponite, kerolite, talc, pyrophyllite, attapulgite,
sepiolite; a mixture of natural silica with a bentonite;any modified clays; and any
mixtures thereof..
[0040] In an embodiment of the present invention, the clay is bentonite.
[0041] In another aspect of the present disclosure, there is provided an encapsulated dye
composition comprising:
- a) a carrier consisting of a mixture of silica and clay
- b) a binder and
- c) dye
wherein said dye is encapsulated in the carrier.
[0042] In an embodiment, the dye is used in the amount in the range of 1% to 30%, based
on the total weight of the encapsulated dye composition, preferably 5% to 20%.
[0043] In an embodiment, the binder is used in the amount of 1 to 5% based on the total
weight of the encapsulated dye composition.
[0044] In an embodiment, the silica is used in the amount of 30% to 75% based on the total
weight of the encapsulated dye composition.
[0045] In an embodiment, the clay is used in the amount of 30% to 75 % based on the total
weight of the encapsulated dye composition.
In an embodiment, the carrier has a silica to clay ratio of 1:4 to 4:1.
In an embodiment the present invention provides an encapsulated dye composition comprising:
- a) a carrier comprising 30% to 75% by weight of silica and 30% to 75% by weight of
clay
- b) 1 to 5% by weight of binder and
- c) 1 to 20% by weight of dye
wherein said dye is encapsulated in the carrier.
[0046] The clay consisting of a smectite like a bentonite, beidellite, saponite, hectorite,
stevensite, kerolite-saponite,is employed in the natural Ca-form or in a soda activated
form.
[0047] In another embodiment natural sodium bentonite is used as clay. Especially preferred
clays are montmorillonites in the natural or soda activated form or mixtures thereof.
[0048] In an embodiment the clay used is bentonite having cation exchange capacity in the
range of 10 meq/100 g to 140 meq/100g.
[0049] In an embodiment the clay used is bentonite having cation exchange capacity in the
range of 20 meq/100 g to 130 meq/100g, preferably between 30 meq/100 g to 120 meq/100
g.
[0050] In an embodiment a special clay mineral is used, which consists of a mixture of smectite
clay and an amorphous silica phase. The clay material is homogenous on a macroscopic
scale, i.e.it is an intimate mixture of both phases.
[0051] The special clay mineral used has a very high silicon content which is well above
the silicon content of e.g. bentonite. The clay mineral does not have such a well
ordered structure as layered silicates, e.g. bentonite, but preferably comprises large
amounts of amorphous material. Such amorphous material is believed to be formed by
amorphous SiO
2.
[0052] The special clay mineral of the present invention comprises a continuous phase of
amorphous silica into which are inserted small platelet-shaped smectite phases. The
platelets of the smectite phase are homogeneously distributed in the continuous amorphous
silica phase and are firmly fixed therein.
[0053] The special clay mineral of the present invention comprises a matrix-like network
of amorphous SiO
2 into which very small clay particles are inserted and which may provide good protection
of the dye to be encapsulated.
[0054] In one embodiment, the clay mineral of the present invention has a very high surface
area in the range of 180 to 300 m
2/g, preferably 185 to 280 m
2/g, and more preferably 190 to 250 m
2/g as determined by the BET method.
[0055] In an embodiment the clay mineral of the present invention has high total pore volume
of more than 0.5 ml/g.
[0056] In an embodiment the clay mineral of the present invention has total pore volume
of more than 0.55 ml/g, preferably more than 0.6 ml/g.
[0057] Inventors believe, the large pore volume of the clay mineral allows rapid access
of the dye particles or molecules to the pores, in which they are protected. The special
clay mineral comprises a matrix of amorphous SiO
2 into which are inserted small particles of smectite minerals. The smectite particles
are delaminated to a high degree and therefore provide a very high surface area.
[0058] Through the large pores provided in the clay mineral, which are in particular situated
in the SiO
2-matrix, a rapid access of the dye to the clay particles inserted in the SiO
2-matrix is possible throughout the absorption process as the clay material does hardly
swell during adsorption of dye.
[0059] In an embodiment the clay mineral used comprise a rigid, amorphous SiO
2 matrix into which are inserted very small clay particles or platelets.
[0060] Preferably, the clay mineral used in the method according to the invention comprises
an amorphous phase of at least 10 wt.% of the total clay mineral, preferably at least
20 wt.%, more preferably at least 30 wt.% .
[0061] In an embodiment of the invention, the amorphous phase forms less than 90 wt.% of
the total clay mineral.
[0062] In another embodiment of the invention, the amorphous phase forms less than 80 wt.%
of the clay mineral.
[0063] Besides the amorphous phase, the clay mineral used in the method of the invention
preferably comprises a smectite phase. The clay mineral preferably comprises less
than 60 wt.%, more preferred less than 50 wt.%, particularly preferred less than 40
wt.% of a smectite phase.
[0064] According to an embodiment of the invention, the smectite phase forms at least 10
wt.%, according to a further embodiment at least 20 wt.% of the clay mineral.
[0065] In an embodiment the ratio of smectite phase to amorphous phase preferably is within
a range of 2 to 0.5, more preferred 1.2 to 0.8.
[0066] Besides the amorphous phase and the smectite phase further minerals may be present
in the clay mineral, preferably within a range of 0.5 to 40 wt.%, more preferred 1
to 30 wt.%, particularly preferred 3 to 20 wt.%. Exemplary side minerals are quartz,
cristobalite, feldspar and calcite. Other side minerals may also be present.
[0067] In accordance with the present invention, the matrix of the clay mineral, preferably
formed from silica gel dilutes the smectite phase which leads, depending on the fraction
of the smectite phase, to a lowering of the signal-to-noise ratio of typical reflections
of smectite minerals e.g. the small angle reflections of montmorillonite are effected
by the periodic distance between layers of the montmorillonite structure. Further,
the clay particles fixed in the SiO
2-matrix are delaminated to a very high degree leading to a strong broadening of the
corresponding diffraction peak.
[0068] The amount of amorphous silica phase and smectite clay phase present in the clay
mineral can be determined by quantitative X-ray-diffraction analysis. Details of such
method are described e.g. in "
Hand Book of Clay Science", F. Bergaya, B.K.G. Therry, G. Lagaly (Eds.), Elsevier,
Oxford, Amsterdam, 2006, Chapter 12.1: I. Srodon, Identification and Quantitative
Analysis of Clay Minerals; "
X-Ray Diffraction and the Identification and Analysis of Clay Minerals", D.M. Moora
and R.C. Reaynolds, Oxford University Press, New York, 1997, pp 765, included herein by reference.
[0070] The quantitative determination of the different minerals in unknown samples is done
by commercially available software, e.g. "Seifert AutoQuan" available from Seifert/GE
Inspection Technologies, Ahrensburg, Germany.
[0071] The XRD-diffractogram of the clay mineral of the present invention exhibit the reflexes
which are hardly visible above noise.
[0072] In an embodiment of the present invention, the signal to noise ratio for reflexes
of the clay mineral, in particular the smectite phase, is close to 1, preferably in
the range of 1 to 1.2. However, the sharp reflexes may be visible in the diffractogram
originating from impurities in the clay mineral, e.g. quartz. Such reflexes are not
considered for determination of the signal/noise ratio.
[0073] In an embodiment, the clay mineral of the present invention, which does not or does
hardly show a 001 reflection indicating the layer distance within the crystal structure
of bentonite particles. Hardly visible means that the signal-to-noise ratio of the
001 reflection of the smectite particles is preferably less than 1.2, particularly
preferred is within a range of 1.0 to 1.1.
[0074] Preferably the clay mineral has a sediment volume in water after 1 hour of less than
15 ml/2g, more preferred of less than 10 ml/2g and most preferred of less than 7 ml/2g.
[0075] In an embodiment the clay mineral of the present invention, in particular when mined
from a natural source, preferably has a cation exchange capacity of more than 40 meq/100
g, particularly preferred of more than 45 meq/100 g and is most preferred selected
within a range of 44 to 120 meq/100 g.
[0076] In an embodiment high activity bleaching earth obtained by extracting a clay mineral
with boiling strong acid is characterized by a very low cation exchange capacity of
usually less than 40 meq/100 g and in most cases of less than 30 meq/100g.
[0077] The modified clay used in the method according to the invention therefore can clearly
be distinguished from such high performance bleaching earth.
[0078] In an embodiment the clay of the present invention is characterized by a high content
of SiO
2 determined after complete disintegration of the clay being above 62 wt.%, preferably
above 64 wt.%, especially preferred above 66 wt.%. Besides silicon other preferred
metals or metal oxides may be contained in the clay. All percentages refer to a dry
clay material dried to constant weight at 105°C.
[0079] The claypreferably has a low aluminium content of, calculated as Al
2O
3, less than 15 wt.%, more preferred of less than 10 wt.%. The aluminium content, calculated
as Al
2O
3, according to an embodiment is more than 2 wt.%, according to a further embodiment
more than 4 wt.%.
[0080] In an embodiment the clay contains magnesium, calculated as MgO, in an amount of
less than 7 wt.%, preferably of less than 6 wt.%, particularly preferred less than
5 wt.%. In one embodiment, the magnesium content is at least 2 wt.%
[0081] In an embodiment the clay contains iron, calculated as Fe
2O
3, in amount of less than 8 wt.%. According to a further embodiment, the iron content,
calculated as Fe
2O
3, may be less than 6 wt.% and according to a still further embodiment may be less
than 5 wt.%. According to a further embodiment, the clay may contain iron, calculated
as Fe
2O
3, in an amount of at least 1 wt.%, and according to a still further embodiment in
an amount of at least 2 wt.%.
[0082] In an embodiment the present invention provides encapsulation of shading dyes comprising
forming an encapsulation matrix consisting of mixture of silica for example hydrophilic
silica or hydrophobic silica, clay, dye and binding agent for example surfactant or
polymers to obtain stable encapsulated dye composition.
[0083] In another aspect the present invention provides method for the preparation of the
encapsulated dye composition.
[0084] The method for preparation of encapsulated dye composition comprises
- a) mixing a dye with a carrier to obtain a mixture;
- b) adding water to the mixture to obtain a semisolid mass;
- c) extruding the semisolid mass to obtain extrudates;
- d) spheronizing the extrudates to obtain granules; and
- e) coating the granules with a binder to obtain the encapsulated dye composition.
[0085] In an embodiment, the encapsulated dye composition can be in the powder form or in
granular form.
[0086] The coating of the granules with the binder can be carried out by the conventionally
known processes.
[0087] In the process of the present invention, the dye is entrapped in the carrier matrix
by simple physical mixing resulting in slightly powder material. Alternatively, granules
are formed by compaction or granulation or by extrusion or by using fluidized bed
processing. The granules thus formed have particle size -400 to 600 microns. Optionally,
the resulting particles can be treated in additional step with liquid barrier materials
like surfactants, aqueous solution of thickening polymers etc.
[0088] The resulting encapsulated dye matrix is not bleeding the dye in powder detergent.
Thus, it is not impacting white powder detergent color. The encapsulated dye is released
in water as desired during the washing cycle.
[0089] In another embodiment the method for preparation of encapsulated dye composition
comprises
- a) mixing the dye with the binder to obtain a mixture.
- b) blending the mixture with silica and clay as carrier to obtain the encapsulated
dye composition.
[0090] In an embodiment the process comprises encapsulation of shading dye Duasyn Acid Violet
4BN-IN (C.I. Acid Violet 17), Duasyn Violet SP-IN (C.I. Direct Violet 66), Duasyn
Red N-6B-IN (C.I. Acid Violet 54), Duasyn Violet FBL-IN (C.I. Acid Violet 48), Duasyn
Red Violet E2R-IN (C.I. Acid Violet 126) or mixtures of one or several of the afore
mentioned dye.
[0091] In another embodiment the dye is suspended in water or used as press cake and is
blended or absorbed on silica and bentonite blends to achieve white dye encapsulated
powder.
[0092] Typically, the process for preparation of encapsulated dye composition comprises
mixing about 5-20% of dye with binder for example 1-5% of polymer or surfactant and
blending this mixture with silica for example Sipernat® D17 optionally followed by
addition of about 5 to 30% of silica for example Ibersil® D100P. The mixture is then
blended thoroughly and the binder is added. The clay bentonites for example 20-40%
of Laundrosil DGA and EXM 0242 is added to the blended mixture which will absorb on
the shading dye loaded silica particles to give the encapsulated dye composition.
This process involves manual/physical mixing of all the ingredients.
[0093] In another embodiment the process for preparation of encapsulated dye composition
comprises fluidized bed coating process to obtain encapsulated matrix of at least
one suitable dye, silica, bentonite and binders which provides spherical particles
having particle size of ∼ 500 micron. Preferably, dye is mixed with silica for example
Sipernat ® 22 and clay in required composition, followed by addition of water to make
dough. The dough is then extruded using extruder and spheronised to prepare granules.
The spheronised granules are further coated using Fluidized Bed Processer with suitable
binding or coating polymers such as Hydroxy Propyl Methyl Cellulose (HPMC), Carboxy
methyl cellulolse (CMC), Polyvinyl alcohol (PVA), polyvinyl acetate (PVAc), and optionally
TiO
2 dispersion for whiteness.
[0094] In accordance with the present invention the encapsulated dye composition comprises
a carrier consisting of a mixture of silica and clay, a dye encapsulated in the carrier
and optionally a binder. The encapsulated dye of the present disclosure is found to
be stable and did not leave stains on the fabric during the washing.
[0095] Surprisingly, the encapsulated dye composition, when used in the detergent powder
does not bleed into the powder and therefore it does not affect the white color of
the detergent powder. Additionally, the encapsulated dye composition is released in
water within few seconds with gentle stirring and can be easily shed off the clothes
during washing.
[0096] In another aspect the present invention provides a detergent composition comprising
encapsulated dye composition comprising:
- a) a carrier comprising 30% to 75% by weight of silica and 20% to 40% by weight of
clay
- b) 1 to 5% by weight of binder and
- c) 1 to 20% by weight of dye
[0097] According to another aspect the present invention provides a method of laundering
fabrics which includes a step of treating the fabrics with detergent composition comprising
the encapsulated dye composition which comprising:
- a) a carrier comprising 30% to 75% by weight of silica and 20% to 40% by weight of
clay
- b) 1 to 5% by weight of binder and
- c) 1 to 20% by weight of dye
[0098] The following examples are provided to better illustrate the present invention and
are not to be interpreted in any way as limiting the scope of the invention. All specific
compositions, materials, and methods described below, in whole or in part, fall within
the scope of the invention. These specific compositions, materials, and methods are
not intended to limit the invention, but merely to illustrate specific embodiments
falling within the scope of the invention. One skilled in the art may develop equivalent
compositions, materials, and methods without the exercise of inventive capacity and
without departing from the scope of the invention. It will be understood that many
variations can be made in the procedures herein described while still remaining within
the bounds of the invention. It is the intention of the inventors that such variations
are included within the scope of the invention.
EXAMPLES
[0099] Following examples disclose various encapsulated dye composition of the present invention
and comparative dye compositions as comparative examples.
Materials and methods:
[0100] Different clays used in the present invention were characterized as follows.
[0101] The physical features used to characterize the adsorbents were ddetermined as follows:
(i) Specific surface and pore volume:
Specific surface and pore volume was determined by the BET-method (single-point method
using nitrogen, according to DIN 66131) with an automatic nitrogen-porosimeter of
Micrometrics, type ASAP 2010. The pore volume was determined using the BJH-method
(
E.P. Barrett, L.G. Joyner, P.P. Hienda, J. Am. Chem. Soc. 73 (1951) 373). Pore volumes of defined ranges of pore diameter were measured by summing up incremental
pore volumina, which were determined from the adsorption isotherm according BJH. The
total pore volume refers to pores having a diameter of 2 to 350 nm. The measurements
provide as additional parameters the micropore surface, the external surface and the
micropore volume. Micropores refer to pores having a pore diameter of up to 2 nm according
to
Pure & Applied Chem. Vol. 51, 603 - 619 (1985).
(ii) Humidity:
The amount of water present in the clay material at a temperature of 105°C was determined
according to DIN/ISO-787/2.
(iii) Silicate analysis/Analysis of the chemical composition (expressed in terms of
SiO
2 and metal oxides):
a) Sample disintegration: A 10 g sample of the clay material was comminuted to obtain
a fine powder which was dried in an oven at 105°C until constant weight. About 1.4
g of the dried sample was deposited in a platinum bowl and the weight is determined
with a precision of 0.001 g. Then the sample was mixed with a 4 to 6-fold excess (weight)
of a mixture of sodium carbonate and potassium carbonate (1:1). The mixture was placed
in the platinum bowl into a Simon-Müller-oven and molten for 2 to 3 hours at a temperature
of 800 - 850°C. The platinum bowl was taken out of the oven and cooled to room temperature.
The solidified melt was dissolved in distilled water and transferred into a beaker.
Then concentrated hydrochloride acid was carefully added. After evolution of gas has
ceased the water was evaporated such that a dry residue was obtained. The residue
was dissolved in 20 ml of concentrated hydrochloric acid followed by evaporation of
the liquid. The process of dissolving in concentrated hydrochloric acid and evaporation
of the liquid was repeated one time. The residue was then moistened with 5 to 10 ml
of aqueous hydrochloric acid (12 %). About 100 ml of distilled water was added and
the mixture was heated. To remove insoluble SiO2, the sample was filtered and the residue remaining on the filter paper was thoroughly
washed with hot hydrochloric acid (12 %) and distilled water until no chlorine was
detected in the filtrate. The clay material was totally disintegrated. After dissolution
of the solids the compounds were analyzed and quantified by specific methods, e.g.
ICP
b) Determination of the SiO2 content
The SiO2 was incinerated together with the filter paper and the residue was weighed.
c) Determination of aluminium, iron, calcium and magnesium
The filtrate was transferred into a calibrated flask and distilled water was added
until the calibration mark. The amount of aluminium, iron, calcium and magnesium in
the solution was determined by FAAS.
c) Determination of potassium, sodium and lithium
A 500 mg sample was weighed in a platinum bowl with a precision of 0.1 mg. The sample
was moistened with about 1 to 2 ml of distilled water and then four drops of concentrated
sulphuric acid were added. About 10 to 20 ml of concentrated hydrofluoric acid was
added and the liquid phase evaporated to dryness in a sand bath. This process was
repeated three times. Finally H2SO4 was added to the dry residue and the mixture was evaporated to dryness on an oven
plate. The platinum bowl was calcined and, after cooling to room temperature, 40 ml
of distilled water and 5 ml hydrochloric acid (18 %) was added to the residue and
the mixture was heated to boiling. The solution was transferred into a calibrated
250 ml flask and water was added up to the calibration mark. The amount of sodium,
potassium and lithium in the solution was determined by EAS.
(iv) Loss on ignition
In a calcined and weighed platinum bowl, about 0.1 g of a sample was deposited weighed
in a precision of 0.1 mg. The sample was calcined for 2 hours at 1000°C in an oven.
Then the platinum bowl was transferred to an exsiccator and weighed.
(v) Ion Exchange capacity
The clay material to be tested was dried at 150°C for two hours. Then the dried material
was allowed to react under reflux with a large excess of aqueous NH
4Cl solution for 1 hour. After standing at room temperature for 16 hours, the material
was filtered. The filter cake was washed, dried, and ground, and the NH
4 content in the clay material was determined by the Kjedahl method. The amount and
kind of the exchanged metal ions was determined by ICP-spectroscopy.
g) Determination of the sediment volume:
A graduated 100 ml glass cylinder was filled with 100 ml of distilled water or with
an aqueous solution of 1 % sodium carbonate and 2 % trisodium polyphosphate. 2 g of
the compound to be analyzed was placed on the water surface in portions of about 0.1
to 0.2 g. After sinking down of a portion, the next portion of the compound was added.
After adding 2 g of the compound to be analyzed the cylinder was held at room temperature
for one hour. Then the sediment volume (ml/2g) was read from the graduation.
h) Determination of montmorillonite proportion by methylene blue adsorption
Preparation of a tetrasodium diphosphate solution
5.41 g tetrasodium diphosphate was weighed with a precision of 0.001 g in a calibrated
1000 ml flask and the flask was filled up to the calibration mark with distilled water
and shaken repeatedly.
Preparation of a 0.5 % methylene blue solution:
In a 2000 ml beaker, 125 g methylene blue was dissolved in about 1500 ml distilled
water. The solution was decanted and then distilled water was added up to a volume
of 25 l.
0.5 g moist test bentonite having a known inner surface were weighed in an Erlenmeyer
flask with a precision of 0.001 g. 50 ml tetrasodium diphosphate solution were added
and the mixture was heated to boiling for 5 minutes. After cooling to room temperature,
10 ml H2SO4 (0.5 m) and 80 to 95 % of the expected consumption of methylene blue solution were
added. With a glass stick a drop of the suspension was transferred to a filter paper.
A blue-black spot was formed surrounded by a colourless corona. Further methylene
blue solution was added in portions of 1 ml and the drop test was repeated until the
corona surrounding the blue-black spot shows a slightly blue colour, i.e. the added
methylene blue was no longer adsorbed by the test bentonite.
i) Analysis of clay materials
The test of the clay material was performed in the same way as described for the test
bentonite. On the basis of the spent methylene blue solution was calculated the inner
surface of the clay material. According to this method 381 mg methylene blue/g clay
correspond to a content of 100 % montmorillonite.
j) Determination of particle size (dry sieve residue)
Through a sieve cloth, a vacuum cleaner connected with the sieve aspirates over a
suction slit circling under the perforated sieve bottom all particles being finer
than the inserted sieve being covered on top with an acrylic glass cover and leaves
the coarser particles on the sieve.
The experimental procedure was as follows: Depending on the product, between 5 and
25 g of air dried material was weighed in and was put on the sieve. Subsequently,
the acrylic glass cover was put on the sieve and the machine was started. During air
jet screening, the screening process can be facilitated by beating on the acrylic
glass cover using the rubber hammer. Exhaustion time was between 1 and 5 minutes.
The calculation of the dry screening residue in % is as follows: actual weight multiplied
with 100 and divided by the initial weight.
k) Apparent weight
A calibrated 1l glass cylinder cut at the 1000 ml mark was weighed. By a powder funnel
the sample was poured into the cylinder in a single step such that the cylinder is
completely filled and a cone was formed on top of the cylinder. The cone was removed
with help of a ruler and material adhering to the outside of the cylinder was removed.
The filled cylinder was weighed again and the apparent weight was obtained by subtracting
the weight of the empty cylinder.
l) X-Ray-Diffraction Analysis
1 to 2 g of clay sample was dry ground by hand in an agate mortar and then passed
through a 20 µm sieve. This process was repeated until the entire sample passed the
sieve. For the X-ray diffraction measurement a Siemens D5000 equipment was used. The
following measuring conditions were employed:
Sample holder |
Plastic, "top loading", Ø = 25 mm |
Thickness of the powder layer |
1 mm |
X-ray tube |
Cu Kα: 40 kV/40mA |
Diffraction angles |
2 - 80 ° (2 θ) |
Measuring time |
3 sec per step |
Slits |
Primary and secondary divergence slits of 1 mm |
[0103] The quantitative evaluation was made according to the Rietveld method as described
above.
Characterization data:
[0104] The clay 1 and 2 namely Bentonite 1 (
Laundrosil® DGA powder) is produced from Bentonite 2 by alkaline activation) and the clay, Bentonite 2 is
a natural calcium/sodium bentonite (EX 0242, from Clariant). Both bentonites powder
exhibit a dry sieve residue of less than 15 wt.% on sieve, with a mesh size of 45
µm.
The following tables show the typical properties of the Bentonite 1 and 2.
Table 1
|
Bentonite 1 |
Bentonite 2 |
Montmorillonite content, determined with the Methylene-blue method [%] |
78 |
75 |
Cation exchange capacity [meq/100 g] |
72 |
76 |
Fraction of monovalent ions of the total cation exchange capacity |
100 |
20 |
Swelling volume in distilled water[ml/2 g) |
> 15 |
11 |
Side mineral content determined by X-ray diffraction |
See below |
See below |
Quarz |
< 1 wt.% |
< 1 wt.% |
Cristobalite |
< 5 wt.% |
< 5 wt.% |
Feldspar |
< 12 wt.% |
< 12 wt.% |
[0105] Characterization details of Clay 3-5 (Clays with High content of SiO
2/Mixed phase of bentonite and natural Silica) is provided in below table. Clay 3 is
sold under the brand name Tonsil® Supreme 118 FF.
Table 2
Clay |
3 |
4 |
5 |
Dry sieve residue on 45 µm (%) |
49 |
55 |
5.2 |
Dry sieve residue on 63 µm (%) |
35 |
40 |
38 |
apparent weight (g/l) |
292 |
468 |
-- |
Methylene blue adsorption (mg/g sample) |
106 |
152 |
179 |
Moisture content (%) |
8 |
13 |
12 |
pH (10 wt.% in water) |
7.6 |
9 |
8.1 |
cation exchange capacity (meq/100 g) |
52 |
44 |
53.3 |
BET surface (m2/g) |
208.4 |
238 |
248 |
micropore area (m2/g) |
32.1 |
40 |
15 |
external surface (m2/g) |
176.3 |
198 |
233 |
micropore volume (cm3/g) |
0.016 |
0.02 |
0.01 |
cumulative pore volume (BJH) for pore diameter 1.7 - 300 nm (cm3/g) |
0.825 |
0.623 |
0.777 |
average pore diameter (BJH) (nm) |
16.4 |
10.0 |
55 |
sediment volume (ml/2g) |
5.5 |
3 |
4 |
[0106] The chemical composition of the adsorbents in clay is summarized in table 3.
Table 3
Clay |
3 |
4 |
5 |
SiO2 |
70.6 wt.% |
69.4 wt.% |
69.4 wt.% |
Fe2O3 |
2.8 wt.% |
3.4 wt.% |
3.4 wt.% |
Al2O3 |
9.8 wt.% |
9.9 wt.% |
9.9 wt.% |
MgO |
4.1 wt.% |
3.1 wt.% |
3.1 wt.% |
CaO |
1.4 wt.% |
2.5 wt.% |
2.5 wt.% |
K2O |
1.5 wt.% |
1.3 wt.% |
1.3 wt.% |
Na2O |
0.26 wt.% |
0.94 wt.% |
0.94 wt.% |
TiO2 |
0.25 wt.% |
0.38 wt.% |
0.38 wt.% |
SO3 |
-- |
-- |
-- |
Loi (1000 °C) |
7.9 wt.% |
8.1 wt.% |
8.1 wt.% |
X-ray diffraction
[0107] X-ray diffraction measurements of clay were made according to the general description
for the method. The results of quantitative mineral phase determination by X-ray diffraction
are listed in table 4.
Table 4
Mineral Phase (wt.%) |
Clay 4 |
Clay 5 |
Smectite |
40 |
40 |
Illite / Muscovite |
Traces |
n.d. |
Kaolinite |
n.d. |
1 |
Sepiolite |
11 |
n.d. |
Quartz |
Traces |
1 |
Orthoclase |
12 |
8 |
Plagioclase (different) |
3 |
11 |
Calcite |
Traces |
1 |
Amorphous material |
34 |
38 |
[0108] The quantitative X-ray diffraction analysis shows presence of smectite clay in clay
1 and 2 which are used in the method according to the invention.
[0109] In addition various side minerals can be found, like sepiolite for clay 1, orthoclase,
plagioclase (other feldspars) and calcite. The X-ray diffraction shows the presence
of more than 30 % of amorphous material for both clays. In clay 2 the amorphous phase
is almost present in the same concentration as the smectite (ratio 100:95), whereas
in clay 1 the ratio of smectite to amorphous material is 100:85.
[0110] The dyes used for making encapsulated dye composition are listed in below table:
Colour Index Name |
Chemical class |
Trade Name |
C.I. Acid Violet 17 |
Triaryl methane dye |
Duasyn Acid Violet 4BN-IN |
C.I. Direct Violet 66 |
Diazo dye |
Duasyn Violet SP-IN |
C.I. Acid Violet 54 |
Azo Dye |
Duasyn Red N-6B-IN |
C.I. Acid Violet 48 |
Anthraquinone Dye |
Duasyn Violet FBL-IN |
C.I. Acid Violet 126 |
Anthraquinone Dye |
Duasyn Red Violet E2R-IN |
[0111] The silica used in the present invention having the properties as listed in the below
table:
Silica Name |
Supplier |
Properties |
|
|
|
Hydrophilic/ Hydrophobic |
Particle Size, d(50) µm |
DOA Absorption, ml/100g |
Tamped Density, g/l |
Sipernat® 22 |
Evonik |
Hydrophilic |
120 |
240 |
245 |
Sipernat® D 17 |
Evonik |
Hydrophobic |
10 |
- |
150 |
Ibersil® D 100 P |
IQESII S.A. |
Hydrophilic |
200 |
245 |
230-280 |
[0112] Comparative examples of encapsulated dye composition using Sipernat® 22
Comparative Example 1:
[0113]
Ingredients |
g |
% |
SIPERNAT® 22 |
8.0 |
80 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
1.0 |
10 |
water |
1.0 |
10 |
Total: |
10 |
100 |
[0114] Method: 8.0g of Sipernat® 22 (Silicon Dioxide, hydrophilic Silica) and 2g of dye
premix containing 1 g of Duasyn Acid Violet 4BN-IN and 1 g of water was mixed manually
to obtain the encapsulated dye composition.
[0115] The encapsulated dye composition was a violet color formulation comprising -10% Duasyn
Acid Violet 4BN-IN.
Comparative Example 2:
[0116]
Ingredients |
g |
% |
SIPERNAT® 22 |
9.0 |
90 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.5 |
5 |
water |
0.5 |
5 |
Total: |
10 |
100 |
[0117] Method: 9.0g of Sipernat® 22 (Silicon Dioxide, hydrophilic Silica) and 1g of dye
premix containing 0.5 g of Duasyn Acid Violet 4BN-IN and 0.5 g of water was mixed
manually to obtain encapsulated dye composition.
[0118] The encapsulated dye composition was a violet color formulation comprising -5% Duasyn
Acid Violet 4BN-IN.
Comparative Example 3:
[0119]
Ingredients |
g |
% |
SIPERNAT® 22 |
4 |
40 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.12 |
1.2 |
water |
5.88 |
58.8 |
Total: |
10 |
100 |
[0120] Method: 4.0g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 6g of dye
premix containing Duasyn Acid Violet 4BN-IN dye and water was mixed manually to obtain
the encapsulated dye composition.
[0121] The dye composition was a violet color formulation comprising ∼1.2 % Duasyn Acid
Violet 4BN-IN.
Comparative Example 4:
[0122]
Ingredients |
g |
% |
SIPERNAT® 22 |
7.5 |
75 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
1.5 |
15 |
HPMC |
0.36 |
3.6 |
water |
0.64 |
6.4 |
Total |
10 |
100 |
[0123] Method: 7.5g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 2.5g of dye
premix containing Duasyn Acid Violet 4BN-IN, HPMC and water were mixed manually to
obtain the encapsulated dye composition. The so obtained dye composition was a violet
color formulation.
Comparative Example 5:
[0124]
Ingredients |
g |
% |
SIPERNAT® 22 |
8.33 |
83.3 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
1.0 |
10 |
HPMC |
0.24 |
2.4 |
water |
0.43 |
4.3 |
Total |
10 |
100 |
[0125] Method: 8.33g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 1.67g of
dye premix containing Duasyn Acid Violet 4BN-IN, HPMC and water were mixed manually
to obtain the encapsulated dye composition. The so obtained dye composition was a
violet color formulation.
Comparative Example 6:
[0126]
Ingredients |
g |
% |
SIPERNAT® 22 |
8.76 |
87.6 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
1.0 |
10 |
HPMC |
0.24 |
2.4 |
Total |
10 |
100 |
[0127] Method: 8.76g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 1.24g of
dye premix containing Duasyn Acid Violet 4BN-IN, HPMC were mixed manually and dried
at 90°C for 1 day (to make it moisture free) to obtain the encapsulated dye composition.
The so obtained dye composition was a faint violet color formulation.
Comparative Example 7
[0128]
Ingredients |
g |
% |
SIPERNAT® 22 |
9.38 |
93.8 |
Dye Premix : |
|
|
Duasyn Acid Violet 4BN-IN |
0.5 |
5 |
HPMC |
0.12 |
1.2 |
Total |
10 |
100 |
[0129] Method : 9.38g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and dye premix
containing Duasyn Acid Violet 4BN-IN and HPMC were mixed manually and dried at 90°C
for 1 day (to make it moisture free) to obtain the encapsulated dye composition. The
so obtained dye composition had faint violet color.
[0130] The following examples are dye compositions prepared according to the present invention:
Example 1
Composition 1:
[0131]
Ingredients |
g |
% |
Sipernat® 22 |
4 |
40 |
Clay 1 (Laundrosil® DGA powder): |
1 |
10 |
Clay 2 (EXM 0242) |
1 |
10 |
Duasyn Acid Violet 4BN-IN 5% Aq. Dispersion: |
|
|
Duasyn Acid Violet 4BN-IN |
0.2 |
2 |
Water |
3.8 |
38 |
Total: |
10 |
100 |
[0132] Method: 4g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica), 1g of Clay 1 Laundrosil®
DGA powder(soda activated bentonite) and Clay 2 EXM 0242 (natural calcium-bentonite)
were mixed to obtain a first mixture. The so obtained first mixture was blended with
4g of 5% aq. dispersion of Duasyn Acid Violet 4BN-IN to obtain the encapsulated dye
composition. During preparation, the mixing was done manually for encapsulation. The
so obtained dye composition was violet color formulation comprising 2% dye. It was
observed that the color becomes more intense after storage at 45°C within a week.
Formulation was found to release dye within few seconds in water with gentle stirring.
Example 2
Composition 2:
[0133]
Ingredients |
g |
% |
Sipernat® 22 |
4 |
40 |
Duasyn Acid Violet 4BN-IN (5% Aq.): |
|
|
Duasyn Acid Violet 4BN-IN |
0.2 |
2 |
Water |
3.8 |
38 |
Clay 1 Laundrosil® DGA powder |
1 |
10 |
Clay 2 EXM 0242 |
1 |
10 |
Total |
10 |
100% |
[0134] Method: 4g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 4g of 5% aq.
dispersion of Duasyn Acid Violet 4BN-IN were mixed to obtain a first mixture. The
so obtained first mixture was blended with 1g of Clay 1 Laundrosil® DGA powder (soda
activated bentonite) to obtain second mixture. Second mixture was mixed with 1g of
Clay 2 EXM 0242 (natural calcium-bentonite) to obtain the encapsulated dye composition.
[0135] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a violet color formulation comprising 2% dye. It was observed
that the color becomes more intense after storage at 45°C within a week. Formulation
was found to release dye within few seconds in water with gentle stirring.
Example 3
Composition 3:
[0136]
Ingredients |
g |
% |
Sipernat® D 17 |
3 |
30 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.5 |
5 |
water |
0.5 |
5 |
Ibersil® D 100 P |
2 |
20 |
Clay1(Laundrosil ® DGA powder |
4 |
40 |
Total |
10 |
100 |
[0137] Method: 3g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 1g of dye
premix containing Duasyn Acid Violet 4BN-IN and water were mixed to obtain a first
mixture. The so obtained first mixture was blended with 2g of Ibersil® D 100 P (Silicon
Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200 micron) to obtain
second mixture. Second mixture was mixed with 4g of Clay 1 (soda activated bentonite,
Laundrosil®DGA powder) to obtain the encapsulated dye composition.
[0138] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a violet color formulation comprising 5% dye. It was observed
that the color becomes more intense after storage at 45°C within a week. Formulation
was found to release dye within few seconds in water with gentle stirring.
Example 4
Composition 4:
[0139]
Ingredients |
g |
% |
Sipernat® D 17 |
2 |
20 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.05 |
0.5 |
water |
0.05 |
0.5 |
Ibersil® D 100 P |
3 |
30 |
Clay 1 (Laundrosil® DGA powder |
4.9 |
49 |
Total |
10 |
100% |
[0140] Method: 2g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 0.1g of dye
premix containing Duasyn Acid Violet 4BN-IN and water were mixed to obtain a first
mixture. The so obtained first mixture was blended with 3g of Ibersil® D 100 P (Silicon
Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200 micron) to obtain
second mixture. Second mixture was mixed with 4.9 g Clay 1 Laundrosil® DGA powder
(soda activated bentonite) to obtain the encapsulated dye composition.
[0141] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -0.5% dye, which was found
to be stable at room temperature (RT) and at 45°C on storage for 2 months. Formulation
was found to release dye within few seconds in water with gentle stirring.
Example 5
Composition 5:
[0142]
Ingredients |
g |
% |
Sipernat® D 17 |
3 |
30 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.6 |
6 |
Water |
0.4 |
4 |
Ibersil® D 100 P |
2 |
20 |
Clay 1 (Laundrosil® DGApowder |
4 |
40 |
Total |
10 |
100 |
[0143] Method: 3g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 1g of dye
premix containing Duasyn Acid Violet 4BN-IN and water were mixed to obtain a first
mixture. The so obtained first mixture was blended with 2g of Ibersil® D 100 P (Silicon
Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain
second mixture. Second mixture was mixed with 4g Clay 1 Laundrosil® DGA powder (soda
activated bentonite) to obtain the encapsulated dye composition.
[0144] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -6% dye, which was found
to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release
dye within few seconds in water with gentle stirring.
Example 6
Composition 6:
[0145]
Ingredients |
g |
% |
Sipernat® D 17 |
2 |
20 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.06 |
0.6 |
water |
0.04 |
0.4 |
Ibersil® D 100 P |
3 |
30 |
Clay 1 (Laundrosil® DGA powder |
4.9 |
49 |
Total |
10 |
100% |
[0146] Method: 2g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 0.1g of dye
premix containing Duasyn Acid Violet 4BN-IN (Triaryl methane dye) and water were mixed
to obtain a first mixture. The so obtained first mixture was blended with 3g of Ibersil®
D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d(50):∼200micron)
to obtain a second mixture. Second mixture was mixed with 4.9g Clay 1 (soda activated
bentonite, Laundrosil® DGA powder) to obtain the encapsulated dye composition.
[0147] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -0.6% dye, which was found
to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release
dye within few seconds in water with gentle stirring.
Example 7
Composition 7:
[0148]
Ingredients |
g |
% |
Sipernat® D 17 |
3 |
30 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.25 |
2.5 |
Duasyn Violet SP-IN |
0.25 |
2.5 |
water |
0.5 |
5 |
Ibersil® D 100 P |
2 |
20 |
Clay 1 (Laundrosil® DGA powder |
4 |
40 |
Total |
10 |
100 |
[0149] Method: 3g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 1g of dye
premix containing 1:1 ratio of Duasyn Acid Violet 4BN-IN and Duasyn Violet SP-IN along
with water were mixed to obtain a first mixture. The so obtained first mixture was
blended with 2g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger
particle size, d (50):∼ 200micron) to obtain second mixture. Second mixture was mixed
with 4g Clay 1 (Laundrosil® DGA powder (soda activated bentonite) to obtain the encapsulated
dye composition.
[0150] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -5% dye, which was found
to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release
dye within few seconds in water with gentle stirring.
Example 8
Composition 8:
[0151]
Ingredients |
g |
% |
Sipernat® D 17 |
2 |
20 |
Dye premix: |
|
|
Duasyn Acid Violet 4BN-IN |
0.025 |
0.25 |
Duasyn Violet SP-IN (1:1) |
0.025 |
0.25 |
water |
0.05 |
0.5 |
Ibersil® D 100 P |
3 |
30 |
Clay 1 (Laundrosil® DGA® powder |
4.9 |
49 |
Total |
|
100 |
[0152] Method: 2g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 0.1g of dye
premix containing 1:1 ratio of Duasyn Acid Violet 4BN-IN and Duasyn Violet SP-IN in
water were mixed to obtain a first mixture. The so obtained first mixture was blended
with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle
size, d (50):∼ 200micron) to obtain a second mixture. Second mixture was mixed with
4.9g Clay 1 Laundrosil® DGA powder (soda activated bentonite) to obtain the encapsulated
dye composition.
[0153] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -0.5% dye and was found to
be stable at RT and at 45°C on storage for 2 months. Formulation was found to release
dye within few seconds in water with gentle stirring.
Example 9
Composition 9:
[0154]
Ingredients |
g |
% |
Dye premix: |
|
|
Duasyn Violet 4BN-IN |
0.7 |
7 |
HPMC |
0.25 |
2.5 |
water |
2.05 |
20.5 |
Sipernat® D17 |
0.5 |
5 |
Ibersil® D 100 P |
3 |
30 |
Mixture of Clay 2 EXM 0242 and Clay 1 (Laundrosil® DGApowder |
3.5 |
35 |
Total |
10 |
100 |
[0155] Method: 3g of dye premix containing Duasyn Violet 4BN-IN, HPMC and water were blended
with Sipernat® D 17 to obtain a first mixture. The so obtained first mixture was blended
with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle
size, d (50):∼ 200micron) to obtain second mixture. Second mixture was mixed with
3.5g blend of Clay 2 EXM 0242 (natural calcium-bentonite) and Clay 1 (Laundrosil®
DGA powder (soda activated bentonite) to obtain the encapsulated dye composition.
[0156] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -7% dye, which was found
to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release
dye within few seconds in water with gentle stirring.
Example 10
Composition 10:
[0157]
Ingredients |
g |
% |
Dye premix: |
|
|
Duasyn Violet SP-IN |
1 |
10 |
HPMC |
0.25 |
2.5 |
Water |
1.75 |
17.5 |
Sipernat® D17 |
0.5 |
5 |
Ibersil® D 100 P |
3 |
30 |
Clay 2 EXM 0242 and Clay 1 (Laundrosil® DGA powder |
3.5 |
35 |
Total |
10 |
100% |
[0158] Method: 3g of dye premix containing Duasyn Violet SP-IN, HPMC and water were blended
with Sipernat D® 17 (Silicon Dioxide, Hydrophobic Silica from Evonik Industries) to
obtain a first mixture. First mixture was mixed with 3g of Ibersil® D 100 P (Silicon
Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain
a second mixture. Second mixture was mixed with 3.5g blend of Clay 2 (EXM 0242) (natural
calcium-bentonite) and Clay 1 Laundrosil® DGA-powder (soda activated bentonite) to
obtain the encapsulated dye composition.
[0159] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -10% dye, which was found
to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release
dye within few seconds in water with gentle stirring.
Example 11
Composition 11:
[0160]
Ingredients |
g |
% |
Dye premix: |
|
|
Duasyn Red N-6B-IN |
1 |
10 |
HPMC |
0.25 |
2.5 |
water |
1.75 |
17.5 |
Ibersil® D 100 P |
3 |
30 |
Clay 2 EXM 0242® and Clay 1 Laundrosil® |
4 |
40 |
DGApowder |
|
|
Total |
10 |
100 |
[0161] Method: 3g of dye premix containing Duasyn Red N-6B-IN, HPMC and water were blended
with Sipernat D® 17 (Silicon Dioxide, Hydrophobic Silica from Evonik Industries) to
obtain a first mixture. The so obtained first mixture was blended with 3g of Ibersil®
D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron)
to obtain second mixture. Second mixture was mixed with 4g blend of Clay 2 EXM 0242
(natural calcium-bentonite) and Clay 1 Laundrosil® DGA powder® (soda activated bentonite)
to obtain the encapsulated dye composition.
[0162] During preparation, the mixing was done manually for encapsulation. The so obtained
dye composition was a white color formulation comprising -10% dye, which was found
to be stable at RT and at 45°C upon storage for 2 months. Formulation was found to
release dye within few seconds in water with gentle stirring. The same formulation
could be prepared using Duasyn Violet FBL-IN, Duasyn Red Violet E2R-IN or mixtures
of two or three dyes mentioned in this example.
Example 12
[0163] Composition 12: The encapsulated dye composition is prepared using Fluidized Bed
Process.
|
Ingredients |
g |
% |
Phase A: Carrier |
Ibersil® D 100 P |
200 |
40 |
Clay 1 Laundrosil® DGApowder |
100 |
20 |
Clay 2 EXM 0242® |
100 |
20 |
Phase B: Dye premix in water |
Duasyn Acid Violet 4BN-IN |
100 |
20 |
Coating solution for Fluidized Bed Processing |
HPMC |
4 |
|
TiO2 (Viscofil White ARCL 30) in water |
10 |
|
[0164] Method: Dye premix containing 100g of Duasyn Acid Violet 4BN-IN dye in water was
mixed with a mixture of 200g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica
with bigger particle size, d (50):∼ 200micron), 100g of Clay 1 Laundrosil® DGA-powder
(soda activated bentonite) and 100g of Clay 2 EX® 0242 (natural Ca-bentonite) in Stephen
mixer to obtain a mixture/dough cake. The mixture/dough cake was extruded through
an extruder to obtain extrudates. The extrudates were spheronized to obtain granules.
Obtained granules were further dried at 45°C in oven to remove any moisture. The granules
were coated with the binder to obtain the encapsulated dye composition. The above
Table shows the final composition of the encapsulated dye composition 12.
[0165] It was observed that the off white HPMC coated beads of the dye composition was stable
at RT and at 45°C for 2 months. The formulation was found to release dye within few
seconds in water with gentle stirring and no dye staining on cloth piece after washing.
Example 13
Composition 13:
[0166]
Ingredients |
g |
% |
Ibersil® D 100 P |
4.02 |
40.2 |
Dye Premix |
|
|
Duasyn Acid Violet 4BN-IN |
1.8 |
18 |
HPMC |
0.18 |
1.8 |
Clay 3 (Tonsil Supreme® 118 FF) |
2 |
20 |
Clay 1 Laundrosil® DGA-powder |
2 |
20 |
Total |
10 |
100 |
[0167] Method: 4.02g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger
particle size, d (50):∼ 200micron) and 3g dye premix containing Duasyn Acid Violet
4BN-IN and HPMC were mixed to obtain a first mixture. The so obtained first mixture
was blended with 2g of Clay 3 Tonsil Supreme® 118 FF to obtain second mixture. Second
mixture was mixed with 2g Clay 1 Laundrosil® DGA-powder (soda activated bentonite)
to obtain the encapsulated dye composition. Encapsulated dye sample was further dried
at 80-90°C for 1 day for complete moisture removal.
[0168] The so obtained dye composition was found to be a white color formulation comprising
-18% Dye. The mixing was done manually for encapsulation. The dye composition was
found to be stable at RT and at 45°C on storage for 2 months. The formulation was
found to release dye within few seconds in water with gentle stirring. The dye composition
was found stable in strength testing. Instead of using Duasyn Acid Violet 4BN-IN for
the premix, alternatively Duasyn Violet SP-IN, Duasyn Red N-6B-IN, Duasyn Violet FBL-IN
or Duasyn Red Violet E2R-IN or a mixture of two or several of the afore mentioned
dye can be used for the preparation of the formulation mentioned in this example.
Example 14
Composition 14:
[0169]
|
Ingredients |
g |
% |
Phase A: Carrier |
Sipernat® 22 |
68 |
34 |
Clay 1 Laundrosil DGA® -powder |
40 |
20 |
Clay 2 EXM 0242® |
40 |
20 |
Phase B: Dye Premix |
|
|
|
Duasyn Violet SP-IN |
40 |
20 |
HPMC |
12 |
6 |
Total |
200 |
100 |
[0170] Method: 52g of phase B, dye premix containing Duasyn Violet SP-IN and HPMC, was mixed
with a mixture of 68g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica), 40g of
Clay 1 Laundrosil DGA®-powder (soda activated bentonite) and 40g of Clay 2 EXM 0242®
in Stephen mixer to obtain a mixture/dough cake. The mixture/dough cake was extruded
through an extruder to obtain extrudates. The extrudates were spheronized to obtain
granules. Obtained granules were further dried at 45°C in oven.
[0171] The dye composition was found to be violet colored granules, which were found to
be stable at RT and at 45°C storage for 2 months. The formulation was found to release
dye within few seconds in water with gentle stirring. The dye composition was found
to be stable in strength testing and no dye staining on cloth piece after washing.
Similar formulations can be prepared with the shading dyes Duasyn Acid Violet 4BN-IN,
Duasyn Red N-6B-IN, Duasyn Violet FBL-IN, Duasyn Red Violet E2R-IN or a mixture of
two or several of the afore mentioned dyes.
Example 15
[0172] Composition 15: The encapsulated dye composition is prepared using Fluidized Bed
Process.
|
Ingredients |
g |
% |
Phase A: Carrier |
Ibersil® D 100 P |
199.5 |
38 |
Laundrosil® DGA-powder |
99.75 |
19 |
|
EXM 0242 |
99.75 |
19 |
Phase B: Dye premix |
Duasyn Acid Violet 4BN-IN |
99.75 |
19 |
Coating |
HPMC |
5.25 |
1 |
Viscofil White ARCL 30 |
21 |
4 |
|
Total = |
525 |
100 |
[0173] Method: Dye premix containing Duasyn Acid Violet 4BN-IN in water was mixed with a
mixture of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle
size, d (50):∼ 200micron), Laundrosil DGA-powder and EXM 0242 (bentonite/Clay) in
Stephen mixer to obtain a mixture/dough cake. The mixture/dough cake was extruded
through an extruder to obtain extrudates. The extrudates were spheronized to obtain
granules. Obtained granules were further dried at 45°C in oven to remove any moisture.
The granules were coated with HPMC and Viscofil White ARCL 30 to obtain the encapsulated
dye composition. The final composition of the encapsulated dye is given in the above
Table.
[0174] The so obtained dye composition was off white color HPMC coated beads, which were
found to be stable at RT and at 50°C on storage for 2 months. The formulation was
found to release dye within few seconds in water with gentle stirring.
[0175] Comparable Formulations can be prepared using Duasyn Violet SP-IN or Duasyn Red N-6B-IN,
Duasyn Violet FBL-IN or Duasyn Red Violet E2R-IN or a mixture of two or several of
the fore mentioned dyes.
Example 16
[0176] Various formulations of the compositions of present invention are tested for their
effects which are discussed as below.
[0177] Methods for testing the encapsulated dye composition of the present invention
A] Open dish stability test
[0178] Method: Open dish stability test was carried out to test the bleeding character of
the encapsulated dye composition. The encapsulated dye composition was mixed with
the white detergent powder and the resulting powder was kept in a petri dish and was
left in the open environment for up to 2 months at room temperature and elevated temperature
to check bleeding.
[0179] Result: It was observed that even after four weeks, the white powder did not change
its color and there was no migration of the dye from the encapsulated dye composition.
Thus, the encapsulated dye composition was found to be stable.
B] Strength of encapsulated samples testing
[0180] Method: The encapsulated dye compositions of the present invention prepared according
to the above examples were used for the strength testing. The encapsulated sample
was added to the powder detergent or components such as sodium sulfate. The sample
was exposed to shear mimicking conditions of mixing dye with powder detergent. The
sample was further observed after strength testing for migration of dye in powder
detergent/sodium sulfate.
[0181] Result: It was observed that dye material was not migrating in powder detergent after
performing the strength testing and white powder was not changing its original color.
C] Dye Staining testing
[0182] Method: The encapsulated dye composition of the present invention prepared according
to the above examples were used for the dye staining test by conventional methods
on the required fabrics such as woven polyester fabric, woven polycotton fabric, woven
cotton CN-II fabric, elastane/nylon fabric.
[0183] Result: It was observed that no stains were left after the washing cycle on the fabric
material. Thus, the encapsulated dye composition was found to be washed out easily
from the fabric.
1. An encapsulated dye composition comprising:
a) carrier consisting of a mixture of silica and clay; and
b) at least one dye encapsulated in the carrier.
2. The composition as claimed in claim 1 further comprises a binder.
3. The composition as claimed in claim 1, wherein said dye is selected from anionic azine
dye or cationic phenazine dye, triaryl-methane dye, triphenyl-methane dye, anthraquinone
dye, azo dye, disazo dye, phthalocyanine dye, quinophthalone dye, methine dye, hemicyanine
dye, azo/azomethine complex dye, triphendioxazine dye or any mixtures thereof.
4. The composition as claimed in claim 3, wherein the dye is selected from the group
consisting of Duasyn Acid Violet 4BN-IN (C.I. Acid Violet 17), Duasyn Violet SP-IN
(C.I. Direct Violet 66), Duasyn Red N-6B-IN (C.I. Acid Violet 54), Duasyn Violet FBL-IN
(C.I. Acid Violet 48), Duasyn Red Violet E2R-IN (C.I. Acid Violet 126) or mixtures
of one or several of the afore mentioned dyes.
5. The composition as claimed in claim 1, wherein said dye is used in the amount in the
range of 1% to 30%, preferably 5% to 20% based on the total weight of the encapsulated
dye composition.
6. The composition as claimed in claim 1, wherein the carrier has a ratio of silica to
clay of from 1:4 to 4:1.
7. The composition as claimed in claim 1, wherein said clay is selected from the group
consisting of natural clays comprising bentonite, montmorillonite, beidellite, saponite,
hectorite, stevensite, kerolite-saponite, kerolite, talc, pyrophyllite, attapulgite,
sepiolite; a mixture of natural silica with a bentonite;any modified clays; and any
mixtures thereof.
8. The composition as claimed in claim 7, wherein the clay contains a natural or sodium
activated bentonite or a mixture containing both.
9. The composition as claimed in claim 7, wherein said clay contains a natural or sodium
activated bentonite with a cation exchange capacity in the range of 10 meq/100 g to
140 meq/100g.
10. The composition as claimed in claim 7, wherein the clay contains a natural or sodium
activated bentonite with a cation exchange capacity in the range of 20 and 130 meq/100g,
preferably in the range of 30 and 120 meq/100 g.
11. The composition as claimed in claim 1, wherein said clay has:
a. a surface area of more than 120 m2/g;
b. a total pore volume of more than 0.35 ml/g;
c. a silicon content, calculated as SiO2, of at least 60 wt.%.
12. The composition as claimed in claim 11, wherein said clay has more than 10 % of amorphous
material as determined by quantitative X-ray diffraction analysis of the mineral phases
of the clay material.
13. The composition as claimed in claim 1, wherein the clay is used in the amount of 30%
to 75% based on the total weight of composition.
14. The composition as claimed in claim 1, wherein the silica is selected from the group
consisting of silica gel, a pyrogenic silica or a precipitated silica or mixtures
thereof.
15. The composition as claimed in claim 14, wherein the silica is a precipitated silica.
16. The composition as claimed in claim 15, wherein the precipitated silica is a hydrophilic
precipitated silica or a hydrophobic precipitated silica or a mixture of both.
17. The composition as claimed in claim 16 wherein the hydrophilic silica has a liquid
carrying capacity determined as DOA absorption number of at least 120 ml/100g, preferably
at least 140 ml/100g, mostly preferred at least 160 ml/100g precipitated silica.
18. The composition as claimed in claim 16 wherein the hydrophilic silica has a particle
size d50 determined by laser diffraction of at least 50 µm, preferably at least 70
µm, mostly preferred at least 90 µm.
19. The composition as claimed in claim 16 wherein the hydrophobic silica has a particle
size d50 determined by laser diffraction of at least 5 µm, preferably at least 7 µm,
mostly preferred at least 9 µm.
20. The dye composition as claimed in claim 1, wherein said silica is used in the amount
of 30% to 75% based on the total weight of the composition.
21. The composition as claimed in claim 2, wherein said binder is a surfactant or a polymer.
22. The composition as claimed in claim 21, wherein said polymer is hydroxyl propyl methyl
cellulose.
23. The composition as claimed in claim 2, wherein the binder is used in the amount of
1 to 5% based on the total weight of the composition.
24. A method for preparing an encapsulated dye composition comprising:
a) mixing a dye with a carrier to obtain a mixture;
b) adding water to the mixture to obtain a semisolid mass;
c) extruding the semisolid mass through an extruder to obtain extrudates;
d) spheronizing the extrudates to obtain granules; and
e) optionally coating the granules with a binder and TiO2 dispersion to obtain the encapsulated dye composition.
25. A method for preparing an encapsulated dye composition comprising:
a) mixing a dye with a carrier to obtain a mixture;
b) adding water, optionally with binder to the mixture to obtain a semisolid mass;
c) extruding the semisolid mass through an extruder to obtain extrudates;
d) spheronizing the extrudates to obtain granules
26. A method for preparing an encapsulated dye composition comprising mixing at least
one dye, silica, clay and binder manually to obtain dye composition encapsulated in
the carrier comprising the steps of
a) mixing a dye with a binder to obtain a first mixture;
b) blending the mixture with a portion of hydrophobic silica to obtain a second mixture;
c) mixing the second mixture with a portion of hydrophilic silica to obtain a third
mixture; and
d) blending the third mixture with a portion of clay to obtain the encapsulated dye
composition.
27. The process as claimed in claim 25 or 26 wherein encapsulated dye composition is obtained
in the powder form or in granular form.
28. Laundry detergent composition comprising encapsulated dye composition comprising carrier
consisting of a mixture of silica and clay; and at least one dye encapsulated in the
carrier.
29. A detergent composition comprising encapsulated dye composition, wherein said dye
composition comprising:
a carrier consisting of 30% to 75% by weight of silica and 30% to 75% by weight of
clay;
1 to 5% by weight of binder; and
1 to 20% by weight of dye.